What causes variation in stovepipe draft?

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PA. Woodsman

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Before the season started I adjusted the bushing that the door latch closes down on in my stove making it a bit looser to close easier and for the first fires of the season weeks ago everything worked fine. These last few fires I noticed more smoke smell upon starting the stove, and thought maybe it had something to do with the gasket on the door not sealing as tight in some spots but if I am correct if anything that might leave a bit more air in the firebox not let anything leak out unless there is a big backpuff so that theory is shot down. I must say these last few fires the weather has been different, colder but the air is damp and heavier last night we got 11" of snow, so I am assuming that the smoke is not able to draft out of the pipe as well until it gets hotter, once it is rolling there is no issue so I am assuming it is that. I even in the dark got a flashlight out and looked very closely to see if I could see any smoke leaking from anywhere on the stove or the pipe but after doing that several times I saw none, so I am assuming that it just has to do with the draft being not as strong right now due to weather conditions, and I do remember having some seasons like that in the past. The pipe was so clean that I didn't even clean it, nothing much there to clean upon inspection, and the only other change was I trimmed some branches off a Pine tree next to the house, don't know if that is a factor or not, and I also can really smell when the neighbors are burning too although the one I know doesn't use wood that is ready to go, smokes like crazy but that's because he doesn't care, but my wood is bone dry from keeping it in the huge double car garage. And the cap is clear, nothing in it like a nest or anything.

Thanks for any input, I haven't changed anything except loosening up the door but I doubt that is causing this sudden change in draft.
 
You said it was clean upon inspection so to me that says you didn't run anything through to snake it out. Maybe you can see your pipe from end to end, I dont know of course but in case you can't. My first thought is to snake it with your chimney scrubber just to make sure its free and clear. Mine I had a nest start in the spring. I pulled a lot of pine straw material out of it then snaked it all the way through. Put a tangle of chicken wire under the cap to keep out birds. Anyway, went to start up a couple weeks ago thinking I was going to be free of nest and ready to go. Just happened to be up on roof with gutter clean out and decided to peek under cap. More sticks and nest material about 7 feet down.

That's my thoughts, I'd make sure to run your scrubber through and eliminate that possiblity.
 
You said it was clean upon inspection so to me that says you didn't run anything through to snake it out. Maybe you can see your pipe from end to end, I dont know of course but in case you can't. My first thought is to snake it with your chimney scrubber just to make sure its free and clear. Mine I had a nest start in the spring. I pulled a lot of pine straw material out of it then snaked it all the way through. Put a tangle of chicken wire under the cap to keep out birds. Anyway, went to start up a couple weeks ago thinking I was going to be free of nest and ready to go. Just happened to be up on roof with gutter clean out and decided to peek under cap. More sticks and nest material about 7 feet down.

That's my thoughts, I'd make sure to run your scrubber through and eliminate that possiblity.
I have a cap that is made so that birds or bats can't get in, plus I looked straight up into it when I inspected it, I took the bottom 4' off inside the house to check that the elbow wasn't rusting out and could shine a flashlight straight up and see that it was clear when I checked how much creosote buildup there which (which wasn't much), so I would eliminate that.
 
I wouldn't mind seeing a pic of your cap, I may need one like it.
It's just one that has a lot of "X's" all around it so nothing can get in, just Google "chimney cap to keep birds (or bats) out and you'll see a wide variety of them.

And on a side note the last log I put in tonight went up like gangbusters, very strong draft at that point. I dozed off and when I woke up it was like a steam bath in there 82 degrees lol!
 
Think you covered it well with surrounding tree branches, outdoor temperature changes and getting the flue warmed up.
Praises for dry fuel. As you say, some do not care to bother, or consider the impact.
You could check to be sure the flue pipe sections are installed correctly, male end down, to keep creosote inside.
No idea if that could effect draft on start up, but good safety check anyway with the others your doing.
Love the wood heat...
 
Damp days and particularly foggy days seem to really reduce my draw. The draw it's all about bouyant warm air rising up the chimney, so a cold chimney or warm outdoor temps compared to inside both reduce the draw. I'm not sure why the damp days do.... Extra moisture in the air leading to a smaller volume change for a given heat input? Anyway, they do, until the flue is warmed by a few hours of stone l stove operation.
Windy days can sometimes give increased draw, Bernoulli and static Vs dynamic head... The wind across the top of the chimney sucking the gases up it.
 
You could check to be sure the flue pipe sections are installed correctly, male end down, to keep creosote inside.
No idea if that could effect draft on start up, but good safety check anyway with the others your doing.
I'm good there, this chimney outside and inside was installed in 1989 and still going just fine, black pipe inside the house stainless steel on the roof so it was installed properly I'm sure.
 
I have similar issues with my chimney. The colder, and or dryer it is out the better the draft. I often think about tearing the chimney down in favor of a double or triple wall stainless pipe. I think they maintain draft better then masonry, but I never thought it was something to be overly concerned about. After an hour or so the draft is great. Warmer weather of shoulder season can be a pain to get a good draft, but I think that's more temperature difference being so close at first then anything.
 
I have similar issues with my chimney. The colder, and or dryer it is out the better the draft. I often think about tearing the chimney down in favor of a double or triple wall stainless pipe. I think they maintain draft better then masonry, but I never thought it was something to be overly concerned about. After an hour or so the draft is great. Warmer weather of shoulder season can be a pain to get a good draft, but I think that's more temperature difference being so close at first then anything.
Do you notice more smoke smell inside until the draft gets better?
 
Do you notice more smoke smell inside until the draft gets better?
Yeah, I just figured it normal, until the chimney get warmed up. It's an 8x8 terracotta chimney so it takes a wile to get warmed up. Once were burning 24/7 it's not an issue. Well always a bit if smoke when you open the feed door, but that's normal as well.
 
Yeah, I just figured it normal, until the chimney get warmed up. It's an 8x8 terracotta chimney so it takes a wile to get warmed up. Once were burning 24/7 it's not an issue. Well always a bit if smoke when you open the feed door, but that's normal as well.

I find it I’m getting a poor draft you can stop the smoke from coming in when you open the door if you do it painfully slow. I usually don’t care as I don’t mine the campfire smell haha.
 
I find it I’m getting a poor draft you can stop the smoke from coming in when you open the door if you do it painfully slow. I usually don’t care as I don’t mine the campfire smell haha.
You are correct, I open the door about 4", hold it there for about 6 seconds or so then open it, and at times I CAN see a little cloud of smoke whisk out almost as to say "ha, I got out anyway!" lol! And even just that little cloud can smell the place up a bit, I usually open the door for a few seconds to allow some fresh air in to dissipate it.

I also notice that the stack temperature is running lower than usual, I have to put more wood in to get the temp on the pipe up where it usually is, so going by that it tells me for some reason the draft is not as strong right now. I seem to remember this happening a few times over the years in the past, but I didn't do any adjustments to the door in those years; I think that is why I am so obsessed with trying to figure this out to see if that made a big change to things, but like I said I added more gasket so that takes care of that issue even if I did change the way the door closes. And it isn't the wood, it is very dry as usual.

And it's 2020, so anything is possible lol!!!

THANKS FOR THE REPLIES, if you think of anything else let me know!
 
I also find that its best to push logs to the back away from the stove door if possible. If I go to load up and there is one smoldering in the front near door, I pull the damper fully open, crack the door and use the poker to push the smoldering log to the back.
I always burn my Lopi Freedom Bay hot and I'll snake the chimney a couple times during burning season, wont get much soot but it always makes it draft that much better.
 
Well I think I figured out what the issue was, I had adjusted the door latch so that it didn't tighten up so darn tight and what that did was loosened up some spots on the door gasket enough to play with the draft. I know that I will eventually have to take the gasket off and put a new one on but that is not real easy as this stove has 3 ways that you have to adjust the door so it lines up correctly, and I just don't have the patience to do that right now. In the meantime I am using a hack that I learned years ago and put some smaller gasket on top of the existing gasket to fill in the gaps, I know it isn't the permanent answer but will work in the short term. Problem is the latch is as tight now if not a bit tighter than it originally was before I messed with it 7 weeks ago lol! But the gasket should flatten out with some time and it will become a bit looser. Just don't feel like wrestling with the door adjustments right now but I will soon.
 
"Put the door tension back where it had been. Simply eliminate that unlikely possibility. Its the only thing you've changed!"

Look familiar :laugh:
I posted this on the other site. Post #6 out of 2 full page's!
Glad you are back on top of things.
 
"Put the door tension back where it had been. Simply eliminate that unlikely possibility. Its the only thing you've changed!"

Look familiar :laugh:
I posted this on the other site. Post #6 out of 2 full page's!
Glad you are back on top of things.
Yes and you were/are right lol!! I didn't think it would change things much but it did, like I said at times I wish this door DIDN'T have so many "options" as it can make you crazy trying to line things up, ugh......
 
Well today I lit a fire and I could see a LOT of orange flame through the left side of the door now.....I cut and put some more gasket on but now the door latches really tight, and it is as loose as it can be, so I guess I'll have to bite the bullet and rip the whole thing off and put a new gasket on, and deal with wrestling with the door to get it lined up again. If it was just an easy thing as replacing the old one and closing it up and letting it dry and curing it with a fire I'd have no hesitation, but this door whenever I put new gasket on it doesn't close, the gasket is very thick and yes it is the correct size, but the door doesn't close, which forces me to loosen the right side and adjust it which means the left side now is out of whack and so on and so on....I at times wish that I had a stove where you just take the old gasket off and replace it and the door closes and all is fine, maybe you have to adjust the latch but that's it. So, here I go!
 
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